Table 4.
Threshold distance for negative margins relative to positive: mean OR (95% CrI) adjusted for follow-up | ||||
---|---|---|---|---|
>0 or 1 mm | 2 mm | 3 mm | 10 mm | |
Main model (N patients) | 2230 | 2412 | 289 | 1963 |
0.45 (0.32-0.61) | 0.32 (0.21-0.48) | 0.30 (0.12-0.76) | 0.32 (0.19-0.49) | |
Sensitivity analysis (N patients) | 1957 | 1851 | 272 | 1079 |
WBRT cohorts only | 0.45 (0.34-0.61) | 0.33 (0.23-0.47) | 0.22 (0.08-0.53) | 0.37 (0.24-0.57) |
Sensitivity analysis (N patients) | 1781 | 1524 | 289 | 616 |
Van Zee et al. excluded | 0.43 (0.31-0.57) | 0.29 (0.19-0.45) | 0.32 (0.14-0.75) | 0.27 (0.16-0.47) |
Sensitivity analysis (N patients) | 2692 | 2555 | 322c | 2160 |
Adding studies with no summary age dataa | 0.44 (0.30-0.63) | 0.31 (0.19-0.51) | 0.32 (0.14-0.73) | 0.20 (0.11-0.35)* |
Adjustment for covariates (based on main model) | ||||
Age | 0.46 (0.33-0.63) | 0.34 (0.22-0.51) | 0.33 (0.13-0.83) | 0.33 (0.20-0.51) |
Median recruitment year | 0.45 (0.31-0.62) | 0.31 (0.19-0.46) | 0.29 (0.12-0.68) | 0.32 (0.20-0.49) |
Proportion with radiotherapy | 0.46 (0.33-0.63) | 0.33 (0.22-0.49) | 0.29 (0.12-0.74) | 0.32 (0.20-0.50) |
Proportion with endocrine therapyb | 0.45(0.29-0.70) | 0.33 (0.18-0.57) | 0.29(0.10-0.79) | 0.31(0.17-0.57) |
Proportion with high grade DCISb | 0.45 (0.32-0.62) | 0.33 (0.21-0.48) | 0.31(0.12-0.74) | 0.39 (0.25-0.59) |
95% CrI for ROR of 10 mm versus >0 or 1 mm did not cross 1.
These studies (from the meta-analysis by Wang et al.) were ineligible for inclusion in our meta-analysis because of lack of summary age data (see eligibility criteria); hence, sensitivity analysis reports estimates if these were included in models
Due to missing covariate information, these analyses were undertaken in a reduced number of studies (19 for endocrine therapy; 16 for high grade DCIS) therefore numbers analysed in these models will be less than those shown in main models. Alternative methods to deal with missing data produced similar results.
Two studies using a 5 mm threshold were included with the 3 mm threshold group.
Abbreviations: CrI = credible interval; DCIS = ductal carcinoma in situ; LR = local recurrence; mm = millimetre; OR = odds ratio; ROR = relative odds ratio; WBRT = whole-breast radiotherapy.